Ultrastructural categorization of human sperm cryopreserved in glycerol and in TESTCY

The motility of human sperm after thawing and the ultrastructural integrity of their acrosomal region was evaluated in 5 semen donors after utilizing 2 cyproprotective extenders--glycerol and TESTCY. Sperm motility in the fresh control semen fraction (65.5% +/- 6.1) was significantly (P less than 0.05) better than the immediate post-thaw motility in both cyprotected fractions (38.8% +/- 2.0 for glycerol and 31.0% +/- 2.9 for TESTCY), and there was no significant difference between the two cyprotective treatments. The overall % of normal intact sperm heads was significantly less than in controls (P less than 0.05) following cypropreservation in glycerol, but values for sperm stored in TESTCY were not significantly different from controls or glycerol. However, when expressed as % change from controls values, sperm preservation was significantly better (P less than 0.05) in TESTCY than in glycerol. TESTCY is considered a better cryoprotective agent for human sperm.